Lifting jack



Oct. 3l, 1944. A. w. HUNz LIFTING JACK Filed Deo. 15, 1941 3Sheets-Sheet 1 r nu /70 lNvENToR. BY @omfe M15/wma' Lay/m/f oct. 31,1944. A, W` HUNZ 2,361,690

LIFTING JACK Filed Dec. l5, 1941 3 Sheets-Sheet 2 Oct. 3l, 1944.

A. W. HUNZ LIFTING JACK Filed Dec. l5, 1941 3 Sheets-Sheet 3 INVENTOK YPatented Oct. 31, 1944 UNITED G JACK Aiphonse'W. Hunz, East Chicago,Indi Applioationeoember 15, 1941, Serial No. 423,079

Claims.'

This invention relates to new and useful im yprovements in lifting jacksand more particularly to such jacks adapted for use in connectionautomobiles and trucks.

An object of the present invention is to pro.- vide a simple andinexpensive mechanical jack which maybe manufactured at extremely lowcost and which `is `positive and efficient in opera tion. l

A further object is to provide a lifting jack comprising a longitudinalbar of angular crosssection having a plurality of teeth integrallyformed therewith and so spaced apart lengthwise of the bar as .to permitthe 1'bar to be shaped by hot-rolling, whereby the bar may readily andinexpensively be formed of high carbon steel, whereby Vthe bar mat7 bemade comparatively Ylight in crossesection and its weight correspondingly reduced, which is a very desirable feature in devices of thisgeneral icharacter.

A further object is to provide a. lifting jack comprising av horizontalbar having a housing slidable thereon and interconnected byV `a 4leverwitha' load-engaging member, and a suitable pawl mechanism being mountedwithin the housingv andengageable with teeth .on the bar, .said pawlmechanism having an operatinghandle and being so constructed that. oneimpulse is. imparted to the housing for each up-stroke .and each down,-stroke of the handle, whereby two impulses .are `inlparted thereto foreach .complete cycle of oper.- ation of the handle, thereby facilitatingthe operf ation of vertically translating the lifting member through'theuse oi levers connected to the vhousiing in either direction.

Other objects of the' invention rreside in the novel construction of thehorizontal `bar of the jack, whereby said bar may readily and conveniently be hot-rolled to facilitate manufacture; in the simple andinexpensive construction of the operating mechanism for the liftinghead, `which comprises a pair of pawls pivotallymounted on a suitableoperating member at opposite sides ofthe pivotal support of Said member,whereby a. double-action is imparted tothe lifting head for eachcomplete stroke of the handle, regardlessof the direction of movement ofthe lift-ing head on the post; in the novel Spring means em ploved forurging the pawls or dogs into engage, ment with the teeth of the bar;andyin the 4means provided for adjusting the pawl mechatnism to reversethe traveling lmovement of the lifting head.

Another object of Athe invention is to providea lifting jack of suchconstruction so that" when f placed, in position thisloalleliitinsheadwill he substantially low .enouehto `permit .the operator fno-place itundertheaxlefof a careonvenently,

Another object/ef the inventionis to provide e lifting heed that-willalso :form a guide as tothe ,Correct position of the placement of theSeck with to theexle;

Another object invention iseto provide a loadAiting-head hav-ing@connected locating or positioning` device which will enable the` operastor to place the .lookin a correct 4posi-tionwittev out the `necessityofA beingforoed to oroueh down on the ground to plaoetne lool:` incorrect po'siF tion,

. Another ,Objectis .to-provide a liiting'head for ythe `jack: to engagedifferent of .the car besides the axlewto raise-the same..

Another object oi the linvention to provide a Jack construction thatwill have a substantial base constructiontha-t will prevent sideslppingofthecar when inlaisedrpositien. Y

`Another .Objectis Vto provide the lifting vhead of the jack .withagauge member-that may or .may not be yused tok gaugethejpositionof thelifting head with respect to the car,

Another objeoaof thenvention-is-to provide a `lack construction thatwillV permit the lifting head to. project beneath thestructure of thecarvand to engage the laxle and-'inse doing also permit the operatinghandle to extend outwardly a suffi nient amount to allow the` jack toheconvenientlv operated. i f

These and other objectsA of the invention will appear from the followingdescriptionand ac companynedrawingsi:

.Figure l is aperspective view of one form of a low level jack -shown inpartly raised position and incorporatingsome of the features of theinvention.

Figure 2 is aside elevational View showing the jaok in itslowerlposition and being shown in dotted lines in itsup or raised position.

Figure r3 is a ,fragmentary sectional view taken on the yline 3*-3 ofFigure 2. g

`Figure Allis a view showing th application of the jack in connectionwith-rasinethe front partofa car;

Figure 5 is a view showing. the ,application of the :look in raising vthel roerend tof anautompbile.'

Figure- 6 isa sectional view taken on the line .l-+6 of Figurelshowingthemechanism for onf' @rating the jack, y ,Y

4liifnires 7 and nrelviewsrsimilar toFignre--' Figure 9 is a plansectional view taken on line 6 9 of Figure 6.

Figure 10 is a sectional view taken on line l-IIJ of Figure 6.

Figure 11 is a view of the pawls and pawl re' taining block.

Figure 12 is a perspective view of a modified construction of a jackwhich is more adaptable to use for heavy loads such as trucks, etc.

Figure 13 `is aside elevational view showing the.

jack in its lowered position in full lines and its raised position indot and dash lines.

Figure 14 is a view of the jack and its adaptation for lifting the frontportionof a car.

Figure 15 is a view of the jack and its adaptation for lifting the sideof a car.

Figure 16 is a detail perspective view of a load lifting member.

As thus illustrated the structure of the jack comprises a longitudinalhorizontal bar 2`having angularly disposed flanges 4 and 6 and havingspaced apart teeth 8 arranged in the bottom of the V formed by theflanges 4 and 6. The forward end of the bar 2 has a flattened portion I0which is welded at I2 to a base plate I4 and having side anges I6 whichform a pivot support for the lever arms I8 through the medium of thepivot pins 2U supported on the anges I6.

The base plate I4 has its forward and rearward edges slightly upturnedas at 22 thereby permitting the jack to be moved backward and forwardmore easily, the upturned edges acting as camming surfaces to slide oversmall obstructions.

Connected by a pivot pin 24 to the lever arms I8 is a bar 26 which hasits opposite endconnectedby `a pivot pin 28 to the lifting head 3U. Thelever arms I 8 are also pvotally connected at .32, to a lever bar 34which in turn has its upper and outward end pivotally connected to theloadlifting head by the pivot pin 36.

, As shown in Figures 1 and 3 the load-lifting head 36 is formed of twosheet metal stampings 4'6 and .42, the one being a right and the otheraf-left, each having a side wall 44 and right angle flanges 46 whichform the load-lifting surface.

They also provide an abutment or wall 48 which isa right angle extensionof the flanges 46and again are bent at an angle to form a liftingsurface 58 which is inclined downwardly to the rear where it convergeswith the wall 48. This surface 56 is substantially lower than thesurface 46, as will be seen in Figure 2, to allow this lifting head tovproject under a very low structure or axle.

In addition the flanges 46 are upturned at the rearward edges to form aslightly curved surface 52 which will accommodate the curved surface ofa leaf spring and also allow the successive leaves of the spring to seatthemselves securely on the lifting head 38 as indicated in Figure 5.

There is also provided a gauging finger 54 pivotally mounted on a pin 55which is supported on the H-bar 34 and has at its outer end a spring 56spaced between the lower end of the nger 54 and a nut 58 threaded on theouter end of the pin-56. The gauge 54 is thus held in any desiredposition due to the pressure of the spring 54 against'it. As willbe'understood from Figure 1 the finger 54 is rotated into a down orinactive position but as shown in Figure 3 and 4 the gauging finger 54is rotated upwardly so that when the jack is positioned under the -axleof a car the gauge-54 will-contact the axle to place the jack in correctposition for raising the car without the necessity of the operator tocrouch downand look under the car structure in order to be sure that theposition of the jack is its proper place with respect to the axle.

Referring again to the load-lifting member 30 it will be noticed inFigure 3 that the pivot pins 28 and 36 also provide spacing membersbetween the two sides 44 to form a cheaply constructed lifting head thathas all the strength and rigidity that is necessary for this type ofjack.

An important feature of the present invention resides in the novelconstruction of the bar 2 which, as shown in Figures l, 6, 10, and 12,is provided with a plurality of spaced teeth 8, arranged in the bottomof the V formed by the angularly disposed flanges 4 and 6 of the bar.The teeth are so shaped and spaced apart lengthwise of the bar as topermit the bar to Ibe readily vand conveniently formed or shaped byhotrolling, whereby it may be made of a suitable high carbon steel. B-ythus hot-rolling the bar of high carbon steel, it may be made extremelylight or small in cross-section, which is highly desirable, in that itmaterially reduces the weight of the jack, when completed, and stillprovides a jack having great strength. To facilitate the operation ofhot-rolling the bar, the teeth 8 thereof are spaced apart approximately5/8 of an inch from center to center; and the oppositely disposed facesof the teeth are beveled, as shown in Figures l and 6.

A suitable housing generally indicated by the numeral 68 embraces thebar 2 and is free to slide longitudinally along the ibar 2 when underthe influence of the pawl operating mechanism 62 which is `positioneddirectly aJbove the bar 2 and between the side walls 64 and 66 of thehousing 60. A pivot pin 68 connects the forward end of the H-bar 34hereinbefore described to the side walls 64 and 66 of the housing 68,the pin 68 being of the same type as the pins III) and I6 which` alsoform spacing and connecting members between the side walls 64 and 66.

As will be noted upon observing Figure l0, the sides 64 and 66 are twoseparate similar members, one being a left-hand member and the other aright-hand member, and both being formed of stampings of suitable gaugesheet metal to provide the necessary strength for this type of jack. Theside walls 64 and 66 are parallel to each other and have their lowermarginal edges turned outwardly at 1I] and then inclined downwardly toform guideways 12 about the flanges 4 and 6 of the bar 2. 'In additionthere is also a pair of inturned flanges 'I4 formed from the side wallsof the housing and which overlie the flanges 4 and 6 of the bar 2 toform a guideway for the housing 60 and also a means for slidablyattaching the housing to the bar 2. In addition there is also a spacingpin or rivet 'I6 positioned at the rear end of the housing 68 which incombination with the other pin 68 -forms a structure that is cheaplymade and provides a housing to enclose the pawl mechanism now to bedescribed.

The jack operating mechanism, as clearly illustrated in Figures 6 to 11inclusive, comprises twoV pawls and 82, the latter being relativelylonger than the pawl 88, and both being produced from standard rodstock, and each pawl having formed on its forward end a head 84 havingan arcuate bearing surface 86. Also formed below the head is a flattenedarea which is spaced between the head and the rod portion 90, the rodportion 9|)r having ears 92 struck from their surfaces which ears havesmall holes 94 to accommodate the opposite ends of a spring 96. Asuitable reaneignen movable operating handle has one end insertedward'ly extending portion |02 provided with .parallel sideportion |104,and -inturned rmarginal edges |06 which form a rectangular area toreceive a bearing block |08. A pin ||.0 positions the block Hi8 in thehousing |02 and also forms a pivot for the above mentioned assembly inthe housing 82 hereinlbefore described. The pivot ||0 also forms one ofthe spacing members :between the walls 64 and 66. The turnedfinedgesy|06 form a retaining and guide means vagainst the surfaces 88 of thepawls 80 and 82.

On the block |08 are three arcuate cutaway portions H2, H4, and ILS, thecenter cut out sectionforming an aperature for the pin |10 and the other.cut away sections forming arcuate bearing surfaces for. the ends 84 ofthe pawls 80 and 82. It will be noted that the cut away sections arepositioned as closely as possible vto the .center cut .away section|;|4. The purpose of locating the bearing surfaces for the pawls, whichreally amount to pivots for the pawls, so close to the central pivotsection is to increase the power produced by the actuating handle S8acting through the short leverage produced by positioning the pivotpoints of the pawls near the center pivot ||0. Due to this constructionrinto aV socketv |100, said socket having a down the minimum amount ofeffort is needed to raise a great amount of weight. By locating thepivot ||0 between the pivots .4 and H8 of the pawls it will readily benoted .thatwhen the handle .iS` .oscillated about the axis ||0 the pawls8D and 32 will 4alternately...move rforward and backward.

A spring .96 hereinbefore described is so shaped that it is constantlyurging the Dawls 80 and 82 into engagement with the teeth of the bar 2whenthe pawls are in the position shown in Figures 6 and 7 and locateddirectly above the spring and positioned at on the side wall 54 of thehousing is a latching `member |20 having an` inwardly extending lip |24overlying the top section |95 of the spring 9B and also an outwardextension |26 which forms an actuator to rotate the latch and bring thelip against the top of the Y spring to apply pressure against .thespring surfaceil. The ,latch |22 is situated on the outside of thehousing 60 but has the lip A|24 extendf ing, through an arcuate slot inthe side wall 64 of vthe housing 6,2,

In addition the side wall 66 of the housing 6 0 is formed with adiagonal rib |8 .extending inwardly of the side wall 66 and acting as aretaining and bearing surface against which the sides of the pawls 80and 8.2 contact. The oppOSite Sides of the pawls `8|) and .82 are heldin alignment by the spring 9.6. There isalso an extension ||9 of the rib||8 (as shown in Figure 10) to contact the side of the lower pawl 80.

When it is desired to lower the lifting head 30, the latch member |22 isswung to the positionshown in Figure 8, whereby the end portion |24thereof moves out of engagement with the portion |95 of the springv |96.When thus posi tioned, the tension in the spring 24 will 4cause the dogs80 and 82 to alternately move out of engagement with the teeth 8 of thebar 2, when the handleV is oscillated. In other words, vwhen the latchmember |22 is positioned as shown in Figure, and the handle 98 is `inits uppermost positiomas shown in this figure, the spring will cause thelower end `0f the .dog 82 to move out of engagement with the rack bar or.teeth s of the barLwhereby when the handle is moved downwardly from thepositionshown mineure s,

to that shown in Figure 7, the .dog 82 will Vpass the top ofthe toothA., and engage the next succeeding tooth B therebehind. When the dog 82.engages the tooth B, the load is transferred from thepawl to the pawl82, and the spring G5 then causes the dog 80 to .swing out of ensgagement with the tooth C, whereby it will `next engage the tooth D,when the handle is swung upwardly. FromA the foregoing, it will thus benoted that when the latch member |22 is in the position shown in Figure.8, continued manipula, tion .of the handleL 9B will cause the housing62 to travel rearwardly along the bar, .thereby to lower the load.`

.When the latch is in the position shown in Figures 6 and 7. themovement of .the housing on the :bar is reversed, because the latchmember thereby positions the spring so as to :urge fthe dogs intoengagement with the teeth 8 `of the bar, whereby oscillation of thehandle will cause the dogs to `so engage .the teeth .of the har as tocause the housing and load-engaging member to travel outwardlyon thebar.

As hereinbefore mentioned the housing has pivotally fixed to it theH-har .3,4 which in turn t is connected tothe lifting head at 36. Thereefore upon movement ,o f the housing 50 to the right or left along thebar 2 it will causethe lever arm 34 to raise the load-lifting head in asubstantially vertical path.

Referring to the drawings, and particularly to Figure l, it will .beseen that the force .is applied at the' point B8 and the fulcrum is at32, the re..- sistance at'3, therefore this arrangement of levers wouldbe of the rst class. In addition the lifting head 30 is retained in itsupright poE Sition .due to the ,arrangement of the lever 26 and itsconnection with :the lifting head and the links I8.

Furthermore .the novel construction of :the pawl mechanism is such thata double action is cb.-` ,tainct In .other words, for each completecycle of movement of the operating handle, two im.- .pulses are impartedto the lifting head in either direction, depending upon the position ofthe latch 4member |22. It will also be noted that a single springprovides the resilient means for urging both pawls into or `out ofoperative engagement with the teeth of the bar. The latch member |22projects from the housing 62, as shown in Figures 6, 4'7, and 8, wherebythe operator may readily shift it from one position to the other byengaging it with the toe .of his shoe. The construction of the pawlmechanism in the en tire jack is extremely simple and inexpensive,whereby the jack may be manufactured at ex.- tremely low cost. Also,because of the horizontal rack bar being made from high carbon steel,which is possible because its vconstruction is such that it may behotrolled, the jack may be made very light i-n weight, a very desirablefeature an automobile jack. The bar -2 is lcomposed of a single lengthof bar iron of any suitable `cross section, which may be applicable Vforthe purpose.

As shown in Figure 4 the lifting head is engaging ythe front axle of acar, moreover the lift ing head is .situa-ted directly below the axle,due tothe gauging linger 54 contacting the axle and informing theoperator lthat the lifting head is in the correct position. Also notethat the operating handle of the jack is sufficiently out from under thecar to afford easy manipulation.

Referring to Figure 5, it will `be observed that the lifting head iscontacting the leaf spring of the car whichvmay be `desirable in someleases,

although it could bemoved .in to contact 4the rear axle. Inj-eitherinstancetheja'ck is positionedivery easily and without a lot of shiftingback and forth toY get it in the proper position, and. also theactuating handle is always sufficiently exposed'so as notto make itdifficult to operate. t

In some cases it may be necessary to use the dropped down portion of the.lifting head to enable the operator toplace the device under anextremely low axle.. for-instance vwhen a wheel has been completelyremoved and wherein-the axle may be substantially contacting ,theground. In Figures 12v and 13 of the drawings there is shown a modifiedconstructionwherein the lifting power of the jack isincreased by theutilization of 1a combination of levers of the first and second classes.There isv also shown a modified type of load lifting head.

As-it will be understood, therackk barv 2, the

housing 60, and the pawl mechanism 62 are of the'same construction asthat shown in the rst form of the inventionv (Figures l-11) hereinbeforedescribed. The forward end of the rack bar 2 being welded to they baseplate |30 having side flanges |32 and front and rear edges curvedupwardly as at |36, which perform the same function as the edges 22formed on vthe base plate |4 of the hereinbefore described jack.

The flanges |32 provide supports for a pair of leverarms |38 pivotallyattached to the flanges |32 by the pivot pins |40, and having theirupper portions converging to provide a space wherein aqlever bar. |42 ispivotallyattached bya pivot pin |44. A pin 68 on the forward part of thehousing 62 pivotally attaches the lower end of the lever arm |42 to thehousing 62. Pivotally connected at `|46 to the lever arms |38 .isanother lever arm |46 which in turn has attached at |50 to its outerenda pivotally mounted load-lifting head |52,.having load contactingsurface |54 and a right angle gauging surface |56, and being formed of asheetfmetal stamping having marginal edges |60 and side flanges |62,which in .pin |50 on the bar |46. On thefvopposite end of the bar |46there is a beveled off portion |62 (see Figure 13)to allow for clearancewhen the jack is in lowered position. In addition the end of lever |46has a contacting end |64 whichcontactsthe under surface of the lever bar|42 when the jack is raised. Therefore when the jack is operated thehousing 60 moves and applies a force at the point 68 to the lever |42which is fulcrumed at |44, to raise the levers |38 and the 5 pivot |48that supports the load-lifting head |52, and the lever bar |46 beingfulcrumed at |48 and having forceA applied at |64 make it a'lever of theflrst class actuated by a lever of the second class due to the fact thatthe resistance orlever |46 is intermediate of the fulcrum |44 and 68 ofthe lever,|42 Therefore by combining the two arrangements of levers avery powerful lifting action is produced which is needed more when heavyloads are to be raised. Referring to Figure 14, it

Another embodimentof the lifting'head as apa plied to this type of jackis shown in Figures -15 and 16, wherein the construction of the jack isturn have apertures to accommodate the pivot 4-5 substantially the sameas that shown in Figures 1 to 1l', with the exception that the lever 26is eliminated and the H,bar 34 is pivotally attached at `|10 to themodified typeof lifting head |12, which is formed from flat stock andcomprises the load contacting surface |14 and the'upturned flanges |16and the downwardly extending ears |18 `which are provided with apertures|80 to receive the pin |10for the lever 34.

. As shown in Figure 15 the load-lifting head |12 is contacting theunderside of a car frame or channel C, which means that the jack hasbeen moved into position from the side of the car. The running board ofthe car being quite 10W to theground would make it almost impossible forthe operator to know how far he should move the jack under the car inorder for it to be in a correct position with respect to the frame orchannel C without the use of a, gauge or measuring device.

To accommodate such a condition there is provided a gauge bar .|82 whichhas a predetermined length for any specified car and is loosely pivotedat |84 to the load-lifting head |12. The opposite end of the bar |82 isbent at right angles to form a projection |86, which when used will beplaced against the running board of the car as shown in Figure 15. Theoperator, by the use of this gauge bar |82, will be able to position thejack so that the load-lifting head |12 will be in the correct positionwith respect to the frame channel C before the jack is operated to raisethe car. A jack that is supplied with a car will have a correct lengthof gauge bar that will be predetermined-by the distance between thecenter of the frame channel C and the outer edge of the body or runningboard R which may vary in different makes of cars.

Obviously the invention is not limited to the specific forms disclosedherein but is capable of other modifications and changes withoutdeparting from the spirit and scope of the claims appended hereto.

The invention is hereby claimed as follows:

l. A lifting jack comprising a horizontally disposed bar having anangular cross section and provided with a plurality of teeth integrallyformed therewith, said teeth being spaced apart longitudinally of thebar'and located within the angle thereof, a base plate attached to saidbar, a housing containingmechanism to engage said teeth and beingslidable longitudinally on said bar, said housing having spaced apartparallel side walls to contain mechanism to engage said teeth on saidbar, said walls being held in spaced relationship, and having reverselybent flanges to overlie the flanges of said angle bar, said wall flangesbeing bent downwardly at an inclination to conform with the angle of theflanges of said angle bar, a load lifting member, a rst lever having oneend pivoted to said housing and its opposing end pivoted to said loadlifting member, a second lever having pivotal connection with said firstlever and said base plate, operating means for actuating the mechanismin said housing to vertically raise and lower said load lifting means.

2. A lifting jack comprising a horizontally disposed bar having anangular cross-section and provided with a plurality of teeth integrallyformed therewith, said teeth being spaced apart longitudinally of thebar and located within the angle thereof, a housing containing mechanismto engage said teeth and being slidable longitudinally on said bar, saidhousing having spaced apart parallel side walls, pivotally mountedmechanism therein to engage said teeth on said bar, spacing means forholding said walls `in spaced relationship, said spacing means formingpivotal supports for said mechanism, lever actuating means for saidmechanism pivotally connected to said housing to vertically raise andlower the lifting member.

3. A lifting jack comprising a horizontally disposed bar provided with aplurality of teeth integrally formed therewith, said teeth being spacedapart longitudinally of the bar, a housing slidable longitudinally onsaid bar, said housing hav` ing spaced apart walls to contain pawl a'ndlatch mechanism to engage said teeth on said bar, one of said wallsbeing formed with an inclined rib having an extension to form a bearingand guiding surface for said pawl mechanism and the other of said wallssupporting a latch to selectively control said pawl mechanism.

4. A lifting jack comprising a horizontally disposed bar having anangular cross-section and provided with a plurality of teeth integrallyformed therewith, said teeth being spaced apart longitudinally of thebai` and located within the angle thereof, a housing containingmechanism to engage said teeth and being slidable longitudinally on saidbar, said housing supporting a pivotal connection, a pawl-actuatinglever for said connection, said lever having a portion projecting fromsaid housing to receive an operating handle, and having its opposite endformed with interconnected parallel side walls, actuating pawls,engaging the teeth of said bar and a member retained by said side wallsfor pivotally engaging said pawls.

5. A lifting jack comprising a horizontally disposed bar having anangular cross-section and provided with a plurality of teeth integrallyformed therewith, said teeth being spaced apart longitudinally of thebar and located within the angle thereof, a housing containing mechanismto engage said teeth and Abeing slidable longitudinally on said bar,said housing supporting a pivotal connection for a pawl-actuatingmember, said member having a portion projecting from said housing toreceive an operating handle, and having its opposite end formed withparallel side walls, said side walls having parallelinturned edges, pawlmembers guided by said edges in their movement during operation of saidhandle.

6. In a device of the character described, a'

toothed bar, a pair of actuating pawls adapted to engage said teeth onsaid bar, a housing having parallel side walls, said pawls beingdisposed in parallel alignment between the side walls of 'said housing,a lever pivoted to said housing and having spaced walls enclosing apivot block, one of said pawls being substantially of greater lengththan the other pawl and both pawls being pivotally held in spaced apartrelationship by said pivot block, each of said pawls having flatparallel surfaces adjacent their pivotal head to engage inturned edgesof said lever. V

7. A lifting jack comprising a horizontally disposed bar having anangular cross-section` and provided with a plurality of teeth integrallyformed therewith, said teeth being spaced apart longitudinally of thebar and located within the angle thereof, a lifting member, a housingcontaining mechanism to engage said teeth and being slidablelongitudinally on said bar, lever means pivotally connected at one endof said housing 'and having its other end pivotally conneoted to saidlifting member, a fulcrum provided by an intermediate lever pivotallyconnected to the pivot on said housing and to the pivot on said liftingmember, said intermediate lever having fixed pivotal connections withsaid base me'mloer, and intermediate of said base pivot and said rstmentioned fulcrum pivot, another lever, pivotally connected to fulcrum asupporting lever i l and having its opposite end pivotally connected tosaid lifting member, said fulcrum supporting lever being formed of twoidentical bars, each disposed oppositely to each other and both beingformed with lower, intermediate, and upper pivot receiving apertures.

8. A lifting jack having a toothed bar, a base, a housing slidable alongsaid bar, a combination of levers of the first and second class, saidcombination consisting of a lever having a pivoted connection with thehousing, pawl operating mechanism in said housing movable longitudinallyof said toothed bar, the other end of said lever being pivotallyconnected to the end of a second lever in turn pivoted to said base,said second lever having an intermediate pivot for a third orload-lifting lever, said load-lifting lever having a load-lifting headpivoted on its outer end and having its opposite end contacting theunder side of the first mentioned lever between the pivot connection onthe housing and the pivoted connection to said second mentioned lever.

9. A lifting jack comprising a horizontally disposed, toothed bar, abase plate attached thereto, a housing slidable along said bar, amechanism in said housing to engage said toothed bar, a load liftingmember, a first lever having one end pivoted to said housing and havingits opposite end pivoted to'saicl load lifting member, a second leverhaving pivotal connections with said rst lever and said base plate,means for operating the mechanism in said housing to vertically raiseand lower said lifting means.

10. In a lifting jack comprising a longitudinal bar, a plurality ofteeth spaced apart longitudinally thereof and integrally formedtherewith and located Within the confines of the bar, the interdentalrecesses in cross section transversely of the bar being curved tofacilitate rolling of the bar, said curved surface being formed by theinterdental walls spreading outwardly in a direction away from thelowest point of the recesses, a pawl mechanism containing a pair ofpawls for engaging said teeth, said pawls being similarly curved andadapted to be received in the interdental recesses, a support slidablelongitudinally along said bar andcontaining said pawl mechanism, liftingmeans connected to said support,

' and operating means for translating said support thereby moving saidlifting means.

ALPHONSE W. HUNZ.

